<!DOCTYPE html>
<html>
<head>
<meta name="viewport" content="width=device-width, initial-scale=1, user-scalable=no">
</head>
<body>
<p>Test passes if you see a single 100px by 100px green box below.</p>
<style>
* { outline: none; }
div { width: 100px; height: 100px; background: gray; }
div:focus { background: red; }
div:focus-within { color: green; }
</style>
<script src="../../resources/ui-helper.js"></script>
<script>

const host = document.createElement('div');
document.body.appendChild(host);

const shadowRoot = host.attachShadow({mode: 'closed', delegatesFocus: true});
shadowRoot.innerHTML = `
<style>
:host { position: relative; }
div { position: absolute; width: 100px; height: 100px; left: 0px; top: 0px; }
div:focus { background: green; }
</style>
<div id="target" tabindex="0"></div>
<div>Click here</div>`;

async function runTest() {
    testRunner.dumpAsText();

    await UIHelper.activateElement(host);
    await UIHelper.ensurePresentationUpdate();
    await new Promise(requestAnimationFrame);

    const pre = document.body.appendChild(document.createElement('pre'));
    log = (text) => pre.textContent += text + '\n';

    log('document.activeElement: ' + (document.activeElement == host ? 'PASS' : 'FAIL'));
    log('host.activeElement: ' + (shadowRoot.activeElement == shadowRoot.getElementById('target') ? 'PASS' : 'FAIL'));
}

if (window.testRunner)
    UIHelper.wait(runTest());

</script>
</body>
</html>